I have questions about a couple of terms that pop up on the board from time to time. First, what is a power lam? Second, what does it mean for a backing material to "over-power" the core? Thanks.
A power lam in a glass laminated bow extends the riser length, on a one piece or the wedges on a t/d. It pushes the bend out further away from the riser. It also in effect shortens the working length of the limb. It allows one to some extent dictate where and how much the limb bends. Don't really know much at all about wooden bows. I will let someone else answer that.
Over powering is when the tension strength of the back is greater than the compression strength of the core, basically "smooshes" the core fibers in a sense.
Bamboo over black walnut was my learning experience about over-powering the core.
James..........
QuoteOriginally posted by jess stuart:
A power lam in a glass laminated bow extends the riser length, on a one piece or the wedges on a t/d. It pushes the bend out further away from the riser. It also in effect shortens the working length of the limb. It allows one to some extent dictate where and how much the limb bends. Don't really know much at all about wooden bows. I will let someone else answer that.
A powerlam in a wood bow does the same thing...
There is something else a power lam does that you don't hear much about too.
Besides pushing the working section of the limb out further towards the tips, it loads the fades more evenly and stores energy in the pre-load stage when you brace the bow.
This helps out a lot in producing early weight on the draw, and can produce a smoother drawing bow if it's used in concert with the right taper rates in the core, and tip wedges.